The New York Police Department wants the public to know that the figures soon to be gazing down from buildings near a Midtown park are an artist's body casts — not residents poised to jump.

City officials were worried the upcoming outdoor exhibit might spark 911 calls of possible jumpers, so it wanted to alert the public ahead of time, said police spokesman Paul Browne.

On Tuesday, the first sculpture of the installation, called "Event Horizon," was placed on top of a building that houses Pentagram Design's New York offices.

"We have a new staffer here at our offices at 204 Fifth Avenue; he doesn't say much, and spends most of his time up on the roof, gazing at the skyline," the company said on its Web site.

By dusk, the figure -- one of two now up -- was a dark shadow against the sky.

Pushing a stroller through Madison Square Park., Morgan Schulz had to stop and stare-- and take some pictures.

"Looked up, and it looked like there was a guy on the edge of the roof," said Schulz. "The color made it seem like it wasn't quite real. And now, looking at it so life-like, sometimes it shimmers. It almost seems like it's moving."

The work by British artist Antony Gormley consists of 31 life-size figures of the artist's body cast in iron and glass fiber. The sculptures will be installed on pathways, sidewalks and rooftops of buildings surrounding Madison Square Park for an exhibit beginning March 26.

Sara Fitzmaurice, a spokeswoman for the Madison Square Park Conservancy, which is sponsoring the installation, said it was unlikely the work would lead to confusion by the public.

"We feel very confident that New Yorkers and others that are in the area will understand that these are sculptures," she said.

But some early viewers were alarmed by the human figures peering over the rooftops.

Emilia John and Celeste Washington work in the area.

"It's a nude guy!" exclaimed John. "Kids are in the park all the time. They should take it down."

Her co-worker was calmer.

"I think it could stay. It looks good," said Washington. "It's art. It's an attempt at art."

Gormley created the installation for a show in London in 2007 and scouted locations for the New York version. The artist was traveling in Europe on Tuesday and couldn't immediately be reached to talk about the work.

In remarks distributed to the press about the installation, Gormley said he wanted to "play with the city and the people's perceptions."

"My intention is to get the sculptures as close to the edge of the buildings as possible. The field of the installation should have no defining boundary," he said.

Mayor Bloomberg downplayed worries that the statues will scare people.

"I haven’t seen it," confessed the Mayor. "You know, I think that New York will adjust very quickly."

"I don’t think anybody’s going to think it’s somebody jumping, which is the argument against it. We’ve tried to get the message out before others went up so hopefully you will inform everybody and they won’t think so," he said.